前言

CD63也被称为溶酶体相关膜蛋白3（LAMP3），属于四次跨膜蛋白超家族成员，与细胞的活化、黏附、变异及肿瘤的侵袭、转移等有关。CD63是外泌体特异性标志蛋白，为新型药物递送及靶向外泌体提供契机，还可作为肿瘤的潜在标志物（如卵巢癌、肺癌等）。研究人员利用重组CD63蛋白开发多种适配体，用于非侵入型外泌体的检测。CD63靶点的多面性为治疗、诊断和生物医学研究带来新希望。

01 CD63生理学和病理学意义

CD63参与多种细胞进程，在晚期内体和多泡体的细胞蛋白分选中发挥关键作用，促进外泌体形成。通过靶向CD63介导外泌体药物的精准递送有助于实现靶向治疗。在免疫反应中，表达CD63的外泌体有助于抗原呈递并激活CD4+T细胞进行免疫调控。这凸显了CD63在免疫治疗中的重要性及其作为小分子抑制剂靶点的潜力。此外，它与整合素的相互作用控制细胞粘附和迁移。

除了在细胞稳态中的发挥基本功能外，CD63在多种肿瘤中均有表达，可促进肿瘤生长并调节肿瘤微环境，可作为癌症治疗的潜在靶标。此外，研究证明CD63外泌体在卵巢癌和肺癌等特定癌症中差异表达，表明其作为诊断生物标志物的潜在用途，对早期诊断和个性化治疗方案的制定产生影响。

CD63 作为诊断及治疗一体化靶点（源自：https://doi.org/10.1002/adbi.202300078）

02 CD63从实验室到临床应用

CD63靶点的多样性为治疗干预提供了广阔的应用前景。在个性化医疗和靶向治疗中，直接或间接地将治疗药物添加到外泌体中已成为一种新的策略。这一创新的方案为精确治疗和疗效改善奠定了基础。值得一提的是，作为创新药物递送载体--细胞来源的胞外囊泡（EVs）已在癌症治疗的研究中如火如荼地开展，其表面表达CD9、CD63、CD81和CD82标记物。这些源自植物细胞、间充质细胞、T细胞和树突状细胞的外泌体具有作为有效药物载体的潜力，对多种疾病的治疗发挥作用。除了其治疗潜力外，CD63存在于外泌体和循环囊泡中，使其适用于从生物体液中进行非侵入性检测。这一先天优势为疾病早期诊断和持续监测开辟了新的途径。截至2023年8月，已有2项针对CD63的临床前研究。

临床试验中CD63靶向药物列表 来源：https://data.pharnexcloud.com/

03 CD63在研究中的应用

CD63重组蛋白可用于新型核酸适体的开发。张振团队开发了一种无需分离纯化、基于适体的荧光偏振检测外泌体的方法（AFPExo）。AFPExo通过荧光偏振检测外泌体，为临床研究分析外泌体提供了一种可靠的方案。刘静团队进行的另一项研究，鉴定出一种新的核酸适体LL4A，用于CD63高表达的PLX4032耐药黑色素瘤患者的预后及靶向治疗。通过抗体或抑制剂阻断CD63的表达，并使用LL4A作为CD63 siRNA的递送工具，有望成为威罗菲尼（Vemurafenib）的新型联合疗法一个潜在新选择。

A. AFPExo法测定外泌体的选择性。使用5.0 μg/mL的CD63和BSA进行检测，结果显示外泌体特异性结合CD63。B. 荧光偏振随CD63浓度变化的曲线图（插图为荧光偏振对ΔFP的线性图），结果显示外泌体对CD63表现出高灵敏度，随CD63浓度的增加而增加。（源自：https://doi.org/10.1039/C9NR01589B）

通过一系列实验证实CD63是LL4A的结合靶点，图为酶联寡核苷酸测定法（ELONA）测定纯化的CD63重组蛋白（货号：11271-H08H，His标签，义翘神州）与LL4A的解离常数。（源自：https://doi.org/10.1016/j.omtn.2019.10.005）

✦义翘神州CD63明星产品

高纯度：

CD63 Protein, Mouse, Recombinant (His Tag), HPLC-verified, Cat: 50557-M08H

Purity ≥ 95 % as determined by SDS-PAGE, ≥ 95 % as determined by SEC-HPLC.

CD63 Protein, Human, Recombinant ( hFc Tag), HPLC-verified, Cat: 11271-H02H

Purity ≥ 95 % as determined by SDS-PAGE, ≥ 95 % as determined by SEC-HPLC.

相关应用: FCM, ICC/IF

Anti-CD63 Antibody, Mouse MAb,  Cat: 11271-MM03

Immunofluorescence staining of CD63 in MCF7 cells.

相关应用: IHC-P

Anti-CD63 Antibody, Mouse MAb,  Cat: 11271-MM01

Immunochemical staining of human CD63 in human malignant melanoma.

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